Color fill block turn pure black after moving
Sometime when you drag multiple section each with different colors fills(gradient or pure color) simultaneously,
One of the section will turn into pure black( it's black not other color maybe because I use pure black fill to draw line contours?)
I try to cut the block and move the rest first, then paste the block and move it, but it will still turn black or even vanish .
But this situation is not frequently occurs, it seems totally random to me.
Is it a glitch or with a reasonable cause, because it's really annoying and inconvenient.
I believe this problem has been discussed before, but I don't know what key word should I use to search it.
If this is well discuss somewhere else, can anyone provide me a link to the article? thank you.

